netcore/System.Private.CoreLib/shared/Interop/Windows/Kernel32/Interop.QueryPerformanceFrequency.cs

   1 // Licensed to the .NET Foundation under one or more agreements.
   2 // The .NET Foundation licenses this file to you under the MIT license.
   3 // See the LICENSE file in the project root for more information.
   4
   5 using System.Runtime.InteropServices;
   6
   7 internal static partial class Interop
   8 {
   9     internal static partial class Kernel32
  10     {
  11         // The actual native signature is:
  12         //      BOOL WINAPI QueryPerformanceFrequency(
  13         //          _Out_ LARGE_INTEGER* lpFrequency
  14         //      );
  15         //
  16         // We take a long* (rather than a out long) to avoid the pinning overhead.
  17         // We don't set last error since we don't need the extended error info.
  18
  19         [DllImport(Libraries.Kernel32, ExactSpelling = true)]
  20         internal static extern unsafe BOOL QueryPerformanceFrequency(long* lpFrequency);
  21     }
  22 }